Why Does My AC Keep Freezing Up?
by The Cooling Company, on Jun 7, 2018 10:24:00 AM
It almost seems counter-intuitive that an air conditioner could freeze over, especially in the summer months out here in Las Vegas where it's unbelievably hot outside (and even inside). Right when you need your unit the most, it malfunctions, leaving you with a frozen air conditioner and insanely warm indoors.
What Causes an AC to Freeze Up?
There are a few different problems that could cause your HVAC system to freeze:
Your Thermostat Could Simply Be Malfunctioning
If your thermostat is malfunctioning, it may be working your air conditioner too hard. As your unit runs too long, it's easy for the AC coils to freeze.
You Have Air Flow Problems
The coil on the air conditioning system needs proper air flow to keep the condensation from freezing. Many times, a frozen AC unit is due to air flow problems that have kept warm air from regulating the temperature of this condensation.
The simplest possible solution to this problem is changing your air filter. Dirty air filters can contribute to air flow problems. Be sure to change dirty air filters regularly, and keep in mind that your air conditioner freezing from this issue may be an indicator that you need regular AC maintenance.
However, you may have a broken fan. This could also be a potential cause of your air flow problems as, even if your air filters are clean, there is no mechanism to effectively push the air through the system.
You're Leaking Freon/Coolant
If airflow isn't the problem, it's possible that there's a refrigerant leak. A leak can cause a lack of pressure that mitigates its functionality in absorbing heat and thus causing the coil to freeze over. A temporary solution is to add more refrigerant to the system, but ultimately, you should begin thinking about contacting a contractor to repair or replace your AC system.
You May Have a Blocked Condensate Line
Condensate lines help drain moisture buildup, but if they become clogged (especially near the evaporator coil), the water and coils could freeze.
What to Do When Your AC Unit Freezes Up: How Do You Unfreeze an Air Conditioner?
So your air conditioner has frozen, and you don't want to call an AC company prematurely. What do you do? Here are the steps you can take to unfreeze an air conditioner and ensure that it's not a simple, easily rectified problem that's causing your unit to freeze up.
- Shut the unit off
- Find and clean up any water damage
- Wait for the unit to defrost and the ice to melt (Never CHIP off the ice as you could damage essential components)
- After an hour (possibly more), run just the fan to get some air flowing through the system
- Check the air filters to ensure they're not in need of replacing
Why Does My AC Keep Freezing?
Okay, so you followed the steps above, but your air conditioning unit does it again a few days later. And again a few days after that. Obviously, something is going wrong to warrant this ongoing issue, and you'll want to fix your frozen air conditioner permanently.
Be sure to pay attention when your AC comes back up to see if it is constantly running without ever turning off (which could indicate the issue with your thermostat). Otherwise, the best course of action is to call an HVAC contractor to troubleshoot the issue. Air conditioners have many moving parts, and unfortunately many potential points of failure.
If the AC continues to freeze multiple times after you've replaced the air filters and ruled out the thermostat, you definitely have an issue with either the airflow in your home or a component failure that's causing the coils to freeze. These issues go beyond what the typical homeowner can do, so it's best to contact a professional HVAC company.